Sure you can.  When setting your destination rule you can go to the Context Browser>User Browser>Groups>K2 and select your Active Directory group.

Of course you can create a role in the K2 Workspace which includes the AD group and assign the Role in the destination rule as well.

Thanks! Its making sense now. I just realize that i added a distributon email group and not a AD group. Users are complaining that they cannot action the workflow and getting an error becuase the way they access the workflow is thru the distribution email group mailbox. And when i change this to an actual AD group, they receive the workflow notification separately from their own mailbox and able to action the workflow successfully.

Thanks again for your help

Rupert